Handcrafted koji since 1689- Spanning 8 generations



Kojiya was established in 1689 by Nobuyoshi Kichizaemon, navy captain of the Sendo group of the Saiki clan. After the Tokugawa shogunate issued the Seikoku Edict of 1635 that resulted in closing Japan to the rest of the world, Kichizaemon left the navy and started a koji business. Kojiya produced koji that was used by families to make miso and shoyu.

Today we still use the original koji propagating room. Called a tsuchimuro, the walls are made of clay. Looking up at the ceiling of the tsuchimuro, one can see a large beam that is made from a piece of ship that belonged to the clan of Lord Takasue Mōri. The floor is partially paved with large stones that remain from the days when this area was a loading dock.

The current koji master is 86-year-old Koichi Asari. His daughter, Myoho, took over the reins of running the business side of things when her mother passed away in 2007. At that time, their business was not doing well because fewer people were using koji to make miso and amazaké at home. The eating habits of the Japanese people changed after the end of the war and food manufacturers began to offer convenient, inexpensive, mass-produced soy sauce, miso and other koji-based products. Where there used to be at least one koji shop in every town, now there are less than 1000 shops left in all of Japan.

Myoho realized that in order to sustain their business, she needed to work to reintroduce the modern cook to the use of koji and offer convenient ways to incorporate it into their daily meal preparation. She researched old texts and cookbooks to see how koji was used in cooking in the past and started developing recipes using shio-koji and amazaké. She started using it in everyday cooking and was surprised to discover that dishes prepared using koji were twice as flavorful because koji brings out the umami in food. She started experimenting with using shio-koji and amazaké in place of salt and sugar in many recipes.

Over the past five years Myoho, also known as “Kojiya Woman”,  has devoted herself to popularizing the use of koji. She has developed many recipes and published several cookbooks, has taught cooking workshops all over Japan, and has appeared on  television cooking shows. Now in any bookstore in Japan you can find many books on cooking with koji and shio-koji. Thanks to Myoho’s efforts, there is a resurgence of interest and use of koji in Japan.

We have been proudly serving the people of Saiki for over 300 years and hope to continue for the next 300 years.

First Generation Founder: Kichizaemon Nobuyoshi
Second Generation: Matauemon Nobuie
Third Generation: Kichizaemon Nobumasa
Fourth Generation: Koubeetachibana Masayoshi
Fifth Generation: Isakutachibana Masanobu
Sixth Generation: Asari Kisuke
Seventh Generation: Asari Nao
Since 1950- Eighth Generation: Asari Koichi